(19)

(11)

EP 0 227 776 A1

(12)

(43) Date of publication: 08.07.1987 Bulletin 1987/28 (21) Application number: 86904251.0 (22) Date of filing: 23.06.1986

(51) International Patent Classification (IPC):  G01G 19/ 32( . ) (86) International application number: PCT/GB1986/000366 (87) International publication number: WO 1986/007630 (31.12.1986 Gazette 1986/28)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 21.06.1985 GB 19850015724 (71) Applicant: MICROSPAN PROCESS CONTROLS LIMITED Maidenhead, Berkshire SL6 8BR (GB)	(72) Inventor: KAY, Joseph, Brian Maidenhead Berkshire SL6 8BR (GB)